The present invention relates to a probing method and apparatus utilizing an optimal probing mode in a prober for inspecting to see whether each of chips formed on a semiconductor wafer is good or bad.
In general, in the process of manufacturing a semiconductor product, a large number of chips are formed so as to be arranged in good order on one sheet of semiconductor wafer. All of these chips are not necessarily a non-defective. Therefore, when the process proceeds to the stage near the final stage, before the semiconductor wafer is cut to produce a plurality of chips, the electrical characteristics of each of the chips are measured with the state of the semiconductor wafer held in order to inspect to see whether each of the chips is a non-defective or a defective.
This measurement is carried out generally using a prober. This prober is provided with a probe card having a large number of probes which are made come in contact with the electrode pads which the individual chips on the semiconductor wafer have. A predetermined inspection signal is applied from the probes to the electrode pads of the individual chips in order to measure the electrical characteristics of the individual chips.
As for a measurement mechanism for such a probe card, there is known the mechanism which has only one measuring channel for use in measuring the electrical characteristics of one chip in order to measure the electrical characteristics of each of the chips one by one in turn. On the other hand, as for a measurement mechanism of the probe card, there is also well known an instrumentation mechanism of a multi-type. The instrumentation mechanism of a multi-type includes one set of measuring channels consisting of a plurality of measuring channels each described above, and measures the electrical characteristics of plural chips using the one set of measuring channels.
As shown in FIG. 6, the above-mentioned probe card of a multi-type has four measuring channels (CH1 to CH4) for example. Each of the measuring channels is provided with a large number of probes which are made come in contact with the respective electrodes of the associated one chip out of a plurality of chips formed on the semiconductor wafer. Then, the electrical signal of each of the chips, which has been obtained from each of the measuring channels (CH1 to CH4) is outputted to a tester 11. Each of the testers inspects, on the basis of the signal, to see whether each chip is a non-defective or a defective.
Then, the probe card of a multi-type is moved successively on the semiconductor wafer in such a way that the prior set of chips formed on the semiconductor wafer do not overlap with the posterior set of chips formed thereon. Whenever the probe card of a multi-type is moved, the probing is carried out in the resultant position.
The probe is moved along a tapered face of the semiconductor wafer while being pressed against the tapered face. As a result, there is a problem that the probe is deformed indicated by a solid line.